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Chemistry
Standard level
Paper 1
Wednesday 10 November 2021 (afternoon)
45 minutes
Instructions to candidates
y Do not open this examination paper until instructed to do so.
y Answer all the questions.
y For each question, choose the answer you consider to be the best and indicate your choice on
the answer sheet provided.
y The periodic table is provided for reference on page 2 of this examination paper.
y The maximum mark for this examination paper is [30 marks].
13 pages
8821 – 6104
© International Baccalaureate Organization 2021
‡
†
89 ‡
Ac
(227)
56
57 †
72
55
Ba
La
Cs
Hf
132.91 137.33 138.91 178.49
6
88
Ra
(226)
38
Sr
87.62
37
Rb
85.47
5
87
Fr
(223)
73
Ta
180.95
39
Y
88.91
20
Ca
40.08
19
K
39.10
4
7
41
Nb
92.91
40
Zr
91.22
21
Sc
44.96
12
Mg
24.31
11
Na
22.99
3
6
90
Th
232.04
58
Ce
140.12
104
Rf
(267)
22
Ti
47.87
91
Pa
231.04
59
Pr
140.91
105
Db
(268)
23
V
50.94
92
U
238.03
60
Nd
144.24
106
Sg
(269)
74
W
183.84
42
Mo
95.96
24
Cr
52.00
Relative atomic mass
Element
4
Be
9.01
Atomic number
5
3
Li
6.94
4
2
3
1
2
1
H
1.01
1
27
Co
58.93
9
28
Ni
58.69
10
29
Cu
63.55
11
30
Zn
65.38
12
6
C
12.01
14
Si
28.09
32
Ge
72.63
13
Al
26.98
31
Ga
69.72
93
Np
(237)
61
Pm
(145)
107
Bh
(270)
14
5
B
10.81
13
33
As
74.92
15
P
30.97
7
N
14.01
15
34
Se
78.96
16
S
32.07
8
O
16.00
16
10
Ne
20.18
18
Ar
39.95
36
Kr
83.90
17
Cl
35.45
35
Br
79.90
2
He
4.00
18
9
F
19.00
17
109
Mt
(278)
110
Ds
(281)
111
Rg
(281)
112
Cn
(285)
113
Unt
(286)
114
Uug
(289)
115
Uup
(288)
83
Bi
208.98
116
Uuh
(293)
84
Po
(209)
117
Uus
(294)
85
At
(210)
94
Pu
(244)
95
Am
(243)
96
Cm
(247)
97
Bk
(247)
98
Cf
(251)
99
Es
(252)
100
Fm
(257)
101
Md
(258)
102
No
(259)
103
Lr
(262)
66
68
64
62
67
69
65
63
70
71
Dy
Sm
Tm
Tb
Lu
Er
Gd
Ho
Eu
Yb
150.36 151.96 157.25 158.93 162.50 164.93 167.26 168.93 173.05 174.97
108
Hs
(269)
82
Pb
207.2
118
Uuo
(294)
86
Rn
(222)
45
48
54
50
46
44
49
51
47
52
53
In
I
Rh
Cd
Xe
Sn
Pd
Ru
Sb
Ag
Te
101.07 102.91 106.42 107.87 112.41 114.82 118.71 121.76 127.60 126.90 131.29
26
Fe
55.85
8
75
80
78
76
81
79
77
Re
Pt
Os
Tl
Au
Ir
Hg
186.21 190.23 192.22 195.08 196.97 200.59 204.38
43
Tc
(98)
25
Mn
54.94
7
The Periodic Table
–2–
8821 – 6104
–3–
1.
8821 – 6104
What is the number of hydrogen atoms in 2.00 moles of Ca(HCO3)2?
Avogadro’s constant, L or NA: 6.02 × 1023 mol−1
2.
3.
A.
2.00
B.
4.00
C.
1.20 × 1024
D.
2.41 × 1024
Which statement describes all homogeneous mixtures?
A.
Any sample has the same ratio of the components.
B.
The components are covalently bonded together.
C.
The components cannot be easily separated.
D.
The mixture needs a specific ratio of components to form.
Which combination is correct?
Structural formula
Empirical formula
IHD
A.
C6H12
C 2H 4
1
B.
C6H14
C 3H 7
0
C.
C 8H 8
CH
3
D.
C8H10
C 4H 6
4
Turn over
–4–
4.
8821 – 6104
The two containers shown are connected by a valve. What is the total pressure after the
valve is opened and the two gas samples are allowed to mix at constant temperature?
Container 2:
volume = 2.0 dm3
pressure = 3.0 × 105 Pa
Container 1:
volume = 4.0 dm3
pressure = 2.0 × 105 Pa
Valve
1.5 × 105 Pa
B.
2.3 × 105 Pa
C.
2.5 × 105 Pa
D.
5.0 × 105 Pa
Consider the mass spectrum of an element:
Relative abundance
5.
A.
4
1
10
11
m/z
What is the relative atomic mass of this element?
A.
10.2
B.
10.5
C.
10.8
D.
10.9
–5–
6.
7.
8.
How many p-orbitals are occupied in a phosphorus atom?
A.
2
B.
3
C.
5
D.
6
Which element has the highest metallic character in Group 14?
A.
C
B.
Si
C.
Ge
D.
Sn
Which combination describes the acid–base nature of aluminium and phosphorus oxides?
Aluminium
9.
8821 – 6104
Phosphorus
A.
Amphoteric oxide
Acidic oxide
B.
Basic oxide
Amphoteric oxide
C.
Acidic oxide
Amphoteric oxide
D.
Amphoteric oxide
Basic oxide
Which molecule has the weakest nitrogen to nitrogen bond?
A.
N2
B.
N 2H 2
C.
N 2H 4
D.
N
N
Turn over
–6–
10.
11.
12.
13.
Which combination would create the strongest ionic bond?
Ionic radius
Charges on ions
A.
large
high
B.
large
low
C.
small
high
D.
small
low
Which compound contains both ionic and covalent bonds?
A.
CH3COONa
B.
CH3COOH
C.
K2O
D.
CaCl2
The following compounds have similar relative molecular masses. What is the order of
increasing boiling point?
A.
CH3CH2CH2OH < CH3CH2CHO < CH3COOH
B.
CH3CH2CHO < CH3CH2CH2OH < CH3COOH
C.
CH3CH2CHO < CH3COOH < CH3CH2CH2OH
D.
CH3COOH < CH3CH2CHO < CH3CH2CH2OH
Which alcohol is least soluble in water?
A.
CH3OH
B.
CH3CH2OH
C.
CH3CH2CH2OH
D.
CH3CH2CH2CH2OH
8821 – 6104
–7–
14.
8821 – 6104
Which combustion reaction releases the least energy per mole of C3H8?
Approximate bond enthalpy / kJ mol−1
15.
16.
O=O
500
C=O
800
C≡O
1000
A.
C3H8 (g) + 5O2 (g) → 3CO2 (g) + 4H2O (g)
B.
C3H8 (g) +
C.
C3H8 (g) + 4O2 (g) → CO2 (g) + 2CO (g) + 4H2O (g)
D.
C3H8 (g) +
9
O (g) → 2CO2 (g) + CO (g) + 4H2O (g)
2 2
7
O (g) → 3CO (g) + 4H2O (g)
2 2
Which equation represents the standard enthalpy of formation of lithium oxide?
A.
4Li (s) + O2 (g) → 2Li2O (s)
B.
2Li (s) +
C.
Li (s) +
1
1
O2 (g) → Li2O (s)
4
2
D.
Li (g) +
1
1
O2 (g) → Li2O (g)
4
2
1
O (g) → Li2O (s)
2 2
Which statement describes an endothermic reaction?
A.
The bonds broken are stronger than the bonds formed.
B.
The enthalpy of the reactants is higher than the enthalpy of the products.
C.
The temperature of the surroundings increases.
D.
The products are more stable than the reactants.
Turn over
–8–
17.
8821 – 6104
Which instrument would best monitor the rate of this reaction?
2KI (aq) + Cl2 (aq) → 2KCl (aq) + I2 (aq)
18.
A.
Balance
B.
Colorimeter
C.
Volumetric flask
D.
Gas syringe
Which combination has the greatest rate of reaction at room temperature?
Zinc
19.
CuSO4 (aq)
A.
1.00 g Zn powder
50.0 cm3 of 0.200 mol dm−3 CuSO4 (aq)
B.
1.00 g Zn powder
100.0 cm3 of 0.100 mol dm−3 CuSO4 (aq)
C.
1.00 g Zn strip
50.0 cm3 of 0.200 mol dm−3 CuSO4 (aq)
D.
1.00 g Zn strip
100.0 cm3 of 0.100 mol dm−3 CuSO4 (aq)
The equilibrium 2H2 (g) + N2 (g)  N2H4 (g) has an equilibrium constant, K, at 150 C.
What is the equilibrium constant at 150 C, for the reverse reaction?
N2H4 (g)  2H2 (g) + N2 (g)
20.
A.
K
B.
K −1
C.
−K
D.
2K
Which ions are present in an aqueous solution of Na2CO3?
I.
HCO3−
II.
OH−
III.
CO32−
A.
I and II only
B.
I and III only
C.
II and III only
D.
I, II and III
–9–
21.
22.
8821 – 6104
What is the conjugate acid of HS−?
A.
H 2S
B.
S2−
C.
H2SO3
D.
H2SO4
What is the change in the oxidation state of oxygen?
2Fe2+ (aq) + H2O2 (aq) + 2H+ (aq) → 2H2O (l) + 2Fe3+ (aq)
23.
A.
+1
B.
0
C.
−1
D.
−2
Which statement is correct about the electrolysis of molten lead(II) bromide, PbBr2?
A.
Br− ions accept electrons at the cathode (negative electrode).
B.
Pb2+ ions accept electrons at the anode (positive electrode).
C.
Br− ions lose electrons at the anode (positive electrode).
D.
Pb2+ ions lose electrons at the cathode (negative electrode).
Turn over
– 10 –
24.
8821 – 6104
Consider this voltaic cell, where Cu is a more reactive metal than Ag:
Wire
Wire
V
Voltmeter
Cu (s) electrode
Cu2+ (aq)
Ag (s) electrode
Salt bridge
Ag+ (aq)
Which combination describes the movement of charge in this cell?
Flow of electrons in wire
Flow of negative ions
in salt bridge
A.
Ag (s) to Cu (s)
Toward Ag+ (aq)
B.
Cu (s) to Ag (s)
Toward Ag+ (aq)
C.
Ag (s) to Cu (s)
Toward Cu2+ (aq)
D.
Cu (s) to Ag (s)
Toward Cu2+ (aq)
– 11 –
25.
8821 – 6104
What is the name of this substance using IUPAC rules?
H
H
C
H
O
H
C
H
H
C
C
H
H
H
C
C
H
H
H
C
H
H
H
H
26.
27.
A.
2-ethyl-1-methylbutan-1-ol
B.
1-methyl-2-ethylbutan-1-ol
C.
3-ethylpentan-2-ol
D.
3-ethylpentan-4-ol
Which pair of compounds are structural isomers?
A.
Propane and propene
B.
Propanal and propanone
C.
Propan-1-ol and propanal
D.
Propyl propanoate and propanoic acid
What is the general formula of alkynes?
A.
CnH2n + 2
B.
CnH2n
C.
CnH2n − 2
D.
C nH n
Turn over
– 12 –
28.
8821 – 6104
What is the slope of the graph?
Reactant concentration / mol dm−3
0.20
0.10
0.05
0.00
0
A.
−0.0025 mol dm−3 s−1
B.
−0.0025 mol dm−3 s
C.
−0.0033 mol dm−3 s−1
D.
−0.0033 mol dm−3 s
20.0
Time / s
40.0
60.0
0
C.
0
0
0
Volume
D.
0
Volume
Pressure
B.
0
Volume
0
Volume
Pressure
A.
Pressure
Which graph shows the relationship between the pressure and volume of a sample of gas at
constant temperature?
Pressure
29.
0.15
0
– 13 –
What can be deduced from the mass spectrum of CH3COCH2CH2CH3?
100
80
Relative intensity
30.
8821 – 6104
60
40
20
0
0
20
40
m/z
60
80
100
A.
The molar mass is 43 g mol−1.
B.
The atoms have many isotopes.
C.
The most likely bond to break is C–C between carbons 2 and 3.
D.
The signal with the largest mass is due to the oxidation of the ketone in the spectrometer.
References:
14.
Chemistry: Atoms First 2e, https://openstax.org/books/chemistry-atoms-first-2e/pages/9-4-strengths-of-ionic-andcovalent-bonds © 1999–2021, Rice University. Except where otherwise noted, textbooks on this site are licensed
under a Creative Commons Attribution 4.0 International License. (CC BY 4.0) https://creativecommons.org/licenses/
by/4.0/.
30.
NIST Mass Spectrometry Data Center Collection © 2021 copyright by the U.S. Secretary of Commerce on behalf
of the United States of America. All rights reserved. 2-Pentanone Mass Spectrum, MS Number 291264. [graph]
Available at: https://webbook.nist.gov/cgi/cbook.cgi?ID=C107879&Units=SI&Mask=200#Mass-Spec2-pentanone
[Accessed 4 May 2020]. Source adapted.
All other texts, graphics and illustrations © International Baccalaureate Organization 2021